The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2003-059868, filed on Mar. 6, 2003, the disclosure of which is incorporated herein by reference in its entirety.
1. Field of the Invention
The present invention relates to reagent injection devices. More particularly, this invention relates to an injection device that injects a specified reagent (which need not but may contain cells, chemicals, etc.) into lesions and other areas of body tissue.
2. Description of the Related Art
In various medical procedures, catheters and other medical apparatuses have traditionally been inserted into components of the cardiovascular system, the gastrointestinal tract, the urinal tract, and other tubular organs of the human body. Recently, as illustrated in Japanese Patent Application Laid-open Nos. 2001-104487 and 2001-299927, reagent injection catheters have been used to inject specific reagents into lesions of body tissues.
Reagent injection catheters of the prior art typically consist of a tubular catheter body, a needle tube, and a needle. The needle usually projects out of the catheter body and pierces various areas of body tissue. However, conventional reagent injection devices are generally equipped with a long, flexible needle tube, which can become bent or retracted upon contact with the relatively hard lesions of body tissue. Consequently, it can be difficult to insert the needle to a desired depth or to a specific position in lesions of body tissues.